"Blackstone's real estate business has had the privilege of working alongside Rockpoint on a number of debt and equity transactions over the years. It is an extraordinarily high-quality and high-integrity investment firm," said Jonathan D. Gray, Blackstone president and chief operating officer, in the news release.

Rockpoint co-founder Bill Walton added in the release: "This permanent capital investment by Blackstone is a testament to our team and investment programs."

The Blackstone investment gives Rockpoint "added visibility and name recognition, as well as access to the highest level processes and procedures, all of which will help strengthen our performance and enhance our franchise," said Caroline Luz, Rockpoint spokeswoman in an email. "Additional benefits will include access to Blackstone's infrastructure and operations services, and strategic support for capital raising and investor relations."